Observation-Conditioned Latent Energy Priors for Sparse Implicit Neural Shape Completion

2026-09-03

AI Summary

该研究提出了一种基于观测条件的潜在能量先验方法，以改进稀疏隐式神经形状补全任务中解码器的表现，通过结合L2潜在先验提高了模型在稀疏样本情况下的性能。

Abstract

Implicit neural representations (INRs) can model continuous 3D shapes with a shared coordinate decoder and per-instance latent codes. At test time, autodecoder-style models commonly freeze the decoder and optimize a new latent code from sparse off-grid SDF samples. When these samples underconstrain inference, the latent can drift toward regions that fit the observations but decode implausible unobserved geometry. We propose a post-hoc observation-conditioned latent energy prior for frozen INR decoders. The energy scores standardized latents conditioned on a permutation-invariant encoding of the sparse observation set and is used as a residual expert alongside an L2 latent prior selected on validation data. We evaluate on a controlled cell-nucleus SDF dataset and a public MedShapeNet-derived SDF completion dataset. The proposed L2 objective augmented with conditional energy improves consistently over a validation-selected L2 baseline in the sparsest cell-nucleus regimes and, on MedShapeNet, outperforms both L2 and a six-component GMM latent-density prior across all reported readouts. A shuffled-context ablation is consistently weaker than matched context, supporting an observation-specific contribution. These results suggest that lightweight conditional energies can make pretrained INR decoders more observation-aware without retraining.

Problem

• Implicit Neural Representations
• Sparse SDF Samples
• Latent Codes
• Shape Completion
• Observation-Conditioned

Innovation

• observation-conditioned latent energy prior
• implicit neural representations (INRs)
• sparse SDF samples
• permutation-invariant encoding
• L2 latent prior